This invention relates generally to a ratchet and, more particularly, to a reversible ratchet for driving a tool such as a socket wrench. As is conventional, the ratchet can be set to drive when turned in a first direction and to free-wheel when turned in the opposite direction. Also, the ratchet can be selectively reversed so as to free-wheel when turned in the first direction and to drive when turned in the opposite direction.
Most commercially available ratchets operate by virtue of the coaction of two toothed members, one of the toothed members usually being in the form of a ring gear in the handle of the ratchet. The toothed members engage one another during driving of the ratchet and then slip past one another as the ratchet free-wheels.
One difficulty with ratchets of this type is that it is often necessary to swing the handle through a substantial angle before the toothed members drivingly re-engage after free-wheeling. As a result, it may not be practical to use the ratchet in tight quarters. While the degree of swing can be reduced by the provision of finer teeth on the toothed members, such teeth tend to shear rather easily and thus the torque capacity of the ratchet is reduced.
Other prior ratchets operate by virtue of one smooth member frictionally engaging another smooth member. Although ratchets of this type drive immediately upon being turned, the drive is not positive as is the case with coacting toothed members. Moreover, the number of components and the critical tolerances of such a ratchet make the ratchet very expensive to manufacture.